import java.util.Arrays;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String str = scanner.next();

        //write your code here......
        StringBuilder stringBuilder = new StringBuilder(str);
        /*for (int i = str.length()-3;i >= 0;i -= 3){
            stringBuilder.insert(i,',');
        }*/
        for (int i = str.length()-4;i >= 0;i -= 4){
            stringBuilder.insert(i,',');
        }
        System.out.println(stringBuilder.toString());
        /*h,ell,owo,rld
        * he,llow,orld*/
    }

}